PROCESS FOR THE TREATMENT OF SKINS, LEATHERS OR COLLAGEN-CONTAINING SHEET MATERIALS USING A PRESSURIZED DENSE FLUID

摘要

Process for the treatment of tanned or non-tanned products comprising skins, leathers or other collagen-containing sheet materials, at different stages in their transformation. According to the process, the products are placed in contact at (1) with a pressurized dense fluid, for example pressurized CO2 in a supercritical or liquid state, which optionally contains one or more active substances and is brought to a pressure Pi at (5) and to a temperature Ti at (7), either for the removal of grease from said products if pure fluid is used, or for their impregnation with active substances such as tanning, reinforcing, dyeing or water-repellent agents. After impregnation or degreasing, the products are brought to ambient pressure for removal of the dense fluid. The process can be carried out at several stages in the transformation of skins into leathers or other sheet materials, fluid pressure and temperature characteristics being adapted to the purpose of the invention.